add quick fix for cast_nullable_to_non_nullable

See: dart-lang/lints#28 Change-Id: Ic0dac81467a3a3fbe7f7bf805ee59e3844edb6a1 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/303681 Reviewed-by: Brian Wilkerson <brianwilkerson@google.com> Commit-Queue: Phil Quitslund <pquitslund@google.com>
dart-lang · May 17, 2023 · 1178e96 · 1178e96
1 parent 1b9198c
commit 1178e96
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Showing 5 changed files with 58 additions and 3 deletions.
diff --git a/pkg/analysis_server/lib/src/services/correction/dart/add_null_check.dart b/pkg/analysis_server/lib/src/services/correction/dart/add_null_check.dart
@@ -16,12 +16,25 @@ import 'package:analyzer_plugin/utilities/fixes/fixes.dart';
 import 'package:analyzer_plugin/utilities/range_factory.dart';
 
 class AddNullCheck extends CorrectionProducer {
+  final bool skipAssignabilityCheck;
+
+  @override
+  final bool canBeAppliedInBulk;
+
   @override
   FixKind fixKind = DartFixKind.ADD_NULL_CHECK;
 
   @override
   List<Object>? fixArguments;
 
+  AddNullCheck()
+      : skipAssignabilityCheck = false,
+        canBeAppliedInBulk = false;
+
+  AddNullCheck.withoutAssignabilityCheck()
+      : skipAssignabilityCheck = true,
+        canBeAppliedInBulk = true;
+
   @override
   Future<void> compute(ChangeBuilder builder) async {
     if (!unit.featureSet.isEnabled(Feature.non_nullable)) {
@@ -80,6 +93,8 @@ class AddNullCheck extends CorrectionProducer {
           target = coveredNode.rightOperand;
         }
       }
+    } else if (coveredNode is AsExpression) {
+      target = coveredNode.expression;
     }
 
     if (target == null) {
@@ -103,6 +118,8 @@ class AddNullCheck extends CorrectionProducer {
     var parent = target.parent;
     if (parent is AssignmentExpression && target == parent.rightHandSide) {
       toType = parent.writeType;
+    } else if (parent is AsExpression) {
+      toType = parent.staticType;
     } else if (parent is VariableDeclaration && target == parent.initializer) {
       toType = parent.declaredElement?.type;
     } else if (parent is ArgumentList) {
@@ -156,6 +173,7 @@ class AddNullCheck extends CorrectionProducer {
       return;
     }
     if (toType != null &&
+        !skipAssignabilityCheck &&
         !typeSystem.isAssignableTo(
             typeSystem.promoteToNonNull(fromType), toType)) {
       // The reason that `fromType` can't be assigned to `toType` is more than

diff --git a/pkg/analysis_server/lib/src/services/correction/error_fix_status.yaml b/pkg/analysis_server/lib/src/services/correction/error_fix_status.yaml
@@ -1989,9 +1989,7 @@ LintCode.cancel_subscriptions:
 LintCode.cascade_invocations:
   status: hasFix
 LintCode.cast_nullable_to_non_nullable:
-  status: needsFix
-  notes: |-
-    The fix is to add an explicit null check (`!`).
+  status: hasFix
 LintCode.close_sinks:
   status: noFix
 LintCode.collection_methods_unrelated_type:

diff --git a/pkg/analysis_server/lib/src/services/correction/fix_internal.dart b/pkg/analysis_server/lib/src/services/correction/fix_internal.dart
@@ -486,6 +486,9 @@ class FixProcessor extends BaseProcessor {
     LintNames.cascade_invocations: [
       ConvertToCascade.new,
     ],
+    LintNames.cast_nullable_to_non_nullable: [
+      AddNullCheck.withoutAssignabilityCheck,
+    ],
     LintNames.combinators_ordering: [
       SortCombinators.new,
     ],

diff --git a/pkg/analysis_server/lib/src/services/linter/lint_names.dart b/pkg/analysis_server/lib/src/services/linter/lint_names.dart
@@ -52,6 +52,8 @@ class LintNames {
   static const String avoid_void_async = 'avoid_void_async';
   static const String await_only_futures = 'await_only_futures';
   static const String cascade_invocations = 'cascade_invocations';
+  static const String cast_nullable_to_non_nullable =
+      'cast_nullable_to_non_nullable';
   static const String combinators_ordering = 'combinators_ordering';
   static const String curly_braces_in_flow_control_structures =
       'curly_braces_in_flow_control_structures';

diff --git a/pkg/analysis_server/test/src/services/correction/fix/add_null_check_test.dart b/pkg/analysis_server/test/src/services/correction/fix/add_null_check_test.dart
@@ -3,6 +3,7 @@
 // BSD-style license that can be found in the LICENSE file.
 
 import 'package:analysis_server/src/services/correction/fix.dart';
+import 'package:analysis_server/src/services/linter/lint_names.dart';
 import 'package:analyzer/error/error.dart';
 import 'package:analyzer/src/error/codes.dart';
 import 'package:analyzer_plugin/utilities/fixes/fixes.dart';
@@ -14,6 +15,7 @@ void main() {
   defineReflectiveSuite(() {
     defineReflectiveTests(AddNullCheckTest);
     defineReflectiveTests(AddNullCheckReplaceWithNullAwareTest);
+    defineReflectiveTests(CastNullableToNonNullableTest);
   });
 }
 
@@ -646,3 +648,35 @@ Iterable<String> f(List<String>? args) sync* {
             error.errorCode != CompileTimeErrorCode.YIELD_EACH_OF_INVALID_TYPE);
   }
 }
+
+@reflectiveTest
+class CastNullableToNonNullableTest extends FixProcessorLintTest {
+  @override
+  FixKind get kind => DartFixKind.ADD_NULL_CHECK;
+
+  @override
+  String get lintCode => LintNames.cast_nullable_to_non_nullable;
+
+  Future<void> test_castNullable() async {
+    await resolveTestCode(r'''
+num? n;
+var i = n as int;
+''');
+    await assertHasFix(r'''
+num? n;
+var i = n! as int;
+''');
+  }
+
+  Future<void> test_castNullable_unnecessaryCast() async {
+    // todo(pq): consider removing unnecessary 'as String' cast
+    await resolveTestCode(r'''
+String? s;
+var a = s as String;
+''');
+    await assertHasFix(r'''
+String? s;
+var a = s! as String;
+''');
+  }
+}